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Encyclopedia > Saturn
Saturn   Astronomical symbol for Saturn
The planet Saturn
Saturn, as seen by Cassini
Orbital characteristics[1][2]
Epoch J2000
Aphelion 1,513,325,783 km
10.11595804 AU
Perihelion: 1,353,572,956 km
9.04807635 AU
Semi-major axis: 1,433,449,370 km
9.58201720 AU
Eccentricity: 0.055723219
Orbital period: 10,832.327 days
29.657 296 yr
Synodic period: 378.09 days[3]
Avg. orbital speed: 9.69 km/s[3]
Mean anomaly: 320.347750°
Inclination: 2.485240°
5.51° to Sun's equator
Longitude of ascending node: 113.642811°
Argument of perihelion: 336.013862°
Satellites: 60 confirmed
(up to 63 seen)
Physical characteristics
Equatorial radius: 60,268 ± 4 km[4][5]
9.4492 Earths
Polar radius: 54,364 ± 10 km[4][5]
8.5521 Earths
Flattening: 0.09796 ± 0.00018
Surface area: 4.27×1010 km²[6][5]
83.703 Earths
Volume: 8.2713×1014 km³[3][5]
763.59 Earths
Mass: 5.6846×1026 kg[3]
95.152 Earths
Mean density: 0.687 g/cm³[3][5]
(less than water)
Equatorial surface gravity: 8.96 m/s²[3][5]
0.914 g
Escape velocity: 35.5 km/s[3][5]
Sidereal rotation period: 0.439 – 0.449 day[7]
(10 h 32 – 47 min)
Rotation velocity at equator: 9.87 km/s[5]
35,500 km/h
Axial tilt: 26.73°[3]
Right ascension of North pole: 2 h 42 min 21 s
40.589°[4]
Declination of North pole: 83.537°[4]
Albedo: 0.342 (bond)
0.47 (geom.)[3]
Surface temp.:
   1 bar level
   0.1 bar
min mean max
134 K[3]
84 K[3]
Apparent magnitude: +1.2 to -0.24 [8]
Angular diameter: 14.5" — 20.1" [3]
(excludes rings)
Adjectives: Saturnian
Atmosphere [3]
Scale height: 59.5 km
Composition:
~96% Hydrogen (H2)
~3% Helium
~0.4% Methane
~0.01% Ammonia
~0.01% Hydrogen deuteride (HD)
0.0007% Ethane
Ices:
Ammonia
water
ammonium hydrosulfide(NH4SH)
Note: This article contains special characters.

Saturn (pronounced /ˈsætɚn/) is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Along with the planets Jupiter, Uranus, and Neptune, it is classified as a gas giant (also known as a Jovian planet, after the planet Jupiter). It was named after the Roman god Saturnus, equated to the Greek Kronos (the Titan father of Zeus) and the Babylonian Ninurta. Saturn's symbol represents the god's sickle (Unicode: ). The day in the week Saturday gets its name from the planet. Saturn may refer to: Saturn, the sixth planet from the Sun in the Solar System Saturn (mythology), the Roman god after whom the planet is named Saturn as a symoblic planet and element in astrology and alchemy Saturn, the Bringer of Old Age, a movement in Gustav Holsts The... Image File history File links Saturn_symbol. ... Image File history File links Size of this preview: 800 × 409 pixel Image in higher resolution (8888 × 4544 pixel, file size: 5. ... Cassini–Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... Two bodies with a slight difference in mass orbiting around a common barycenter. ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... A diagram of Keplerian orbital elements. ... The astronomical unit (AU or au or a. ... A diagram of Keplerian orbital elements. ... The semi-major axis of an ellipse In geometry, the term semi-major axis (also semimajor axis) is used to describe the dimensions of ellipses and hyperbolae. ... (This page refers to eccitricity in astrodynamics. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... Look up day in Wiktionary, the free dictionary. ... In astronomy, a Julian year is a unit of time defined as exactly 365. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... The orbital speed of a body, generally a planet, a natural satellite, an artificial satellite, or a multiple star, is the speed at which it orbits around the barycenter of a system, usually around a more massive body. ... In the study of orbital dynamics the mean anomaly is a measure of time, specific to the orbiting body p, which is a multiple of 2π radians at and only at periapsis. ... For the science fiction novella by William Shunn, see Inclination (novella). ... The Longitude of the ascending node (☊, also noted Ω) is one of the orbital elements used to specify the orbit of an object in space. ... The argument of periapsis (ω) is the orbital element describing the angle between an orbiting bodys ascending node (the point where the body crosses the plane of reference from South to North) and its periapsis (the point of closest approach to the central body), measured in the orbital plane and... A natural satellite is an object that orbits a planet or other body larger than itself and which is not man-made. ... The Saturnian system (photographic montage) Saturn has 60 confirmed natural satellites, plus three hypothetical moons. ... World map showing the equator in red In tourist areas, the equator is often marked on the sides of roads The equator marked as it crosses Ilhéu das Rolas, in São Tomé and Príncipe. ... A geographical pole is either of two fixed points on the surface of a spinning body or planet, at 90 degrees from the equator, based on the axis around which a body spins. ... The flattening, ellipticity, or oblateness of an oblate spheroid is the relative difference between its equatorial radius a and its polar radius b: The flattening of the Earth is 1:298. ... In mathematics, a spheroid is a quadric surface in three dimensions obtained by rotating an ellipse about one of its principal axes. ... For other uses, see Volume (disambiguation). ... For other uses, see Mass (disambiguation). ... For other uses, see Density (disambiguation). ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... The surface gravity of a Killing horizon is the acceleration, as exerted at infinity, needed to keep an object at the horizon. ... Acceleration is the time rate of change of velocity and/or direction, and at any point on a velocity-time graph, it is given by the slope of the tangent to the curve at that point. ... The term g force or gee force refers to the symbol g, the force of acceleration due to gravity at the earths surface. ... Space Shuttle Atlantis launches on mission STS-71. ... On a prograde planet like the Earth, the sidereal day is shorter than the solar day. ... In astronomy, axial tilt is the inclination angle of a planets rotational axis in relation to a perpendicular to its orbital plane. ... Equatorial Coordinates Right ascension (abbrev. ... In astronomy, declination (abbrev. ... For other uses, see Albedo (disambiguation). ... The Bond albedo is the fraction of power in the total electromagnetic radiation incident on an astronomical body that is scattered back out into space. ... The geometric albedo of an astronomical body is the ratio of its total brightness at zero phase angle to that of an idealised fully reflecting, diffusively scattering (Lambertian) disk with the same cross-section. ... For other uses, see Temperature (disambiguation). ... For other uses, see Kelvin (disambiguation). ... The apparent magnitude (m) of a star, planet or other celestial body is a measure of its apparent brightness as seen by an observer on Earth. ... The angular diameter of an object as seen from a given position is the diameter measured as an angle. ... A scale height is a term often used in scientific contexts for a distance over which a quantity decreases by a factor of e. ... This article is about the chemistry of hydrogen. ... General Name, symbol, number helium, He, 2 Chemical series noble gases Group, period, block 18, 1, s Appearance colorless Standard atomic weight 4. ... Methane is a chemical compound with the molecular formula . ... For other uses, see Ammonia (disambiguation). ... Hydrogen deuteride is a bi-atomic compund of the two isotopes of hydrogen: the majority isotope 1H protium and 2H deuterium. ... This article is about a chemical compound. ... For other uses, see Ammonia (disambiguation). ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Ammonium sulfide, (NH4)2S, is obtained, in the form of micaceous crystals, by passing hydrogen sulfide mixed with a slight excess of ammonia through a well-cooled vessel; the hydrosulfide NH4·HS is formed at the same time. ... This article is about the astronomical term. ... Sol redirects here. ... This article is about the Solar System. ... For other uses, see Jupiter (disambiguation). ... For other uses, see Jupiter (disambiguation). ... For other uses, see Uranus (disambiguation). ... For other uses, see Neptune (disambiguation). ... This article does not cite any references or sources. ... Saturnus, Caravaggio, 16th c. ... Cronus is not to be confused with Chronos, the personification of time. ... For other uses, see Zeus (disambiguation). ... Ninurta Lord Plough in Sumerian and Akkadian mythology was the god of Nippur, identified with Ningirsu with whom he may always have been identical. ... Using a sickle A sickle is a curved, hand-held agricultural tool typically used for harvesting grain crops before the advent of modern harvesting machinery. ... The Unicode Standard, Version 5. ... This article or section does not cite its references or sources. ...


The planet Saturn is primarily composed of hydrogen, with small proportions of helium and trace elements.[9] The interior consists of a small core of rock and ice, surrounded by a thick layer of metallic hydrogen and a gaseous outer layer. The outer atmosphere is generally bland in appearance, although long-lived features can appear. Wind speeds on Saturn can reach 1,800 km/h, significantly faster than those on Jupiter. Saturn has a planetary magnetic field intermediate in strength between that of Earth and the more powerful field around Jupiter. This article is about the chemistry of hydrogen. ... General Name, symbol, number helium, He, 2 Chemical series noble gases Group, period, block 18, 1, s Appearance colorless Standard atomic weight 4. ... Metallic hydrogen results when hydrogen is sufficiently compressed and undergoes a phase change; it is an example of degenerate matter. ... For other uses, see Atmosphere (disambiguation). ... This article or section does not adequately cite its references or sources. ... Magnetic field lines shown by iron filings Magnetostatics Electrodynamics Electrical Network Tensors in Relativity This box:      In physics, the magnetic field is a field that permeates space and which exerts a magnetic force on moving electric charges and magnetic dipoles. ...


Saturn has a prominent system of rings, consisting mostly of ice particles with a smaller amount of rocky debris and dust. Sixty known moons orbit the planet. Titan, Saturn's largest and the Solar System's second largest moon (after Ganymede), is larger than the planet Mercury and is the only moon in the Solar System to possess a significant atmosphere.[10] The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... This article is about water ice. ... Debris (French, pronounced (IPA) dibri) is a word used to describe the remains of something that has been otherwise destroyed. ... “Space dust” redirects here. ... Titan (, from Ancient Greek Τῑτάν) or Saturn VI is the largest moon of Saturn and the only moon known to have a dense atmosphere. ... This article is about the natural satellite of Jupiter. ... [[Link titleBold text // ]] This article is about the planet. ...

Contents

Physical characteristics

The Earth is one of Saturn's major satellites.

Due to a combination of its low density, rapid rotation, and fluid state, Saturn is an oblate spheroid; that is, it is flattened at the poles and bulges at the equator. Its equatorial and polar radii differ by almost 10%— 60268 km vs. 54364 km.[3] The other gas planets are also oblate, but to a lesser extent. Saturn is the only planet of the Solar System that is less dense than water. Although Saturn's core is considerably denser than water, the average specific density of the planet is 0.69 g/cm³ due to the gaseous atmosphere. Saturn is only 95 Earth masses,[3] compared to Jupiter, which is 318 times the mass of the Earth[11] but only about 20% larger than Saturn.[12] Image File history File linksMetadata Download high resolution version (1024x888, 266 KB)Rough comparison of sizes of Saturn and Earth. ... Image File history File linksMetadata Download high resolution version (1024x888, 266 KB)Rough comparison of sizes of Saturn and Earth. ... An oblate spheroid is ellipsoid having a shorter axis and two equal longer axes. ... In mathematics, a spheroid is a quadric surface in three dimensions obtained by rotating an ellipse about one of its principal axes. ... World map showing the equator in red In tourist areas, the equator is often marked on the sides of roads The equator marked as it crosses Ilhéu das Rolas, in São Tomé and Príncipe. ... For other uses, see Density (disambiguation). ... The planetary core consists of the innermost layer(s) of a planet. ... For explanation of specific gravity as it relates to renal function, see Specific gravity (kidney). ...


Composition

The outer atmosphere of Saturn consists of about 93.2% molecular hydrogen and 6.7% helium. Trace amounts of ammonia, acetylene, ethane, phosphine, and methane have also been detected.[13] The upper clouds on Saturn are composed of ammonia crystals, while the lower level clouds appear to be composed of either ammonium hydrosulfide (NH4SH) or water.[14] The atmosphere of Saturn is significantly deficient in helium relative to the abundance of the elements in the Sun. For other uses, see Ammonia (disambiguation). ... Acetylene (systematic name: ethyne) is a hydrocarbon belonging to the group of alkynes. ... This article is about a chemical compound. ... This article is about the chemical. ... Methane is a chemical compound with the molecular formula . ... Ammonium sulfide, (NH4)2S, is obtained, in the form of micaceous crystals, by passing hydrogen sulfide mixed with a slight excess of ammonia through a well-cooled vessel; the hydrosulfide NH4·HS is formed at the same time. ...


The quantity of elements heavier than helium are not known precisely, but the proportions are assumed to match the primordial abundances from the formation of the Solar System. The total mass of these elements is estimated to be 19–31 times the mass of the Earth, with a significant fraction located in Saturn's core region.[15]


Internal structure

Saturn's temperature emissions: the prominent hot spot at the bottom of the image is at Saturn's south pole.

Saturn's interior is similar to that of Jupiter, having a small rocky core surrounded mostly by hydrogen and helium. The rocky core is similar in composition to the Earth, but denser. Above this, there is a thicker liquid metallic hydrogen layer, followed by a layer of liquid hydrogen and helium, and in the outermost 1,000 km a gaseous atmosphere. [16] Traces of various ices are also present. The core region is estimated to be about 9–22 times the mass of the Earth.[17] Saturn has a very hot interior, reaching 11,700 °C at the core, and it radiates 2.5 times more energy into space than it receives from the Sun. Most of the extra energy is generated by the Kelvin-Helmholtz mechanism (slow gravitational compression), but this alone may not be sufficient to explain Saturn's heat production. An additional proposed mechanism by which Saturn may generate some of its heat is the "raining out" of droplets of helium deep in Saturn's interior, the droplets of helium releasing heat by friction as they fall down through the lighter hydrogen.[18] Infrared image of saturn showing a warm polar vortex File links The following pages link to this file: Saturn (planet) Categories: NASA images ... Infrared image of saturn showing a warm polar vortex File links The following pages link to this file: Saturn (planet) Categories: NASA images ... Metallic hydrogen results when hydrogen is sufficiently compressed and undergoes a phase change; it is an example of degenerate matter. ... The Kelvin-Helmholtz mechanism is an astronomical event that occurs when the surface of a star or a planet cools. ... For other uses, see Friction (disambiguation). ...


Cloud layers

Saturn's celestial body atmosphere exhibits a banded pattern similar to Jupiter's (the nomenclature is the same), but Saturn's bands are much fainter and are also much wider near the equator. At the bottom, extending for 10 km and with a temperature of -23 °C, is a layer made up of water ice. After that comes a layer of ammonium hydrosulfide ice, which extends for another 50 km and is approximately at -93 °C. Eighty kilometers above that are ammonia ice clouds, where the temperatures are about -153 °C. Near the top, extending for some 200 km to 270 km above the clouds, come layers of visible cloud tops and a hydrogen and helium atmosphere.[19] Saturn's winds are among the Solar System's fastest. Voyager data indicate peak easterly winds of 500 m/s (1,800 km/h).[9] Saturn's finer cloud patterns were not observed until the Voyager flybys. Since then, however, Earth-based telescopy has improved to the point where regular observations can be made. Atmosphere is the general name for a layer of gases that may surround a material body of sufficient mass. ... Voyager Project redirects here. ... This article is about Earth as a planet. ... This article does not cite any references or sources. ...


Saturn's usually bland atmosphere occasionally exhibits long-lived ovals and other features common on Jupiter. In 1990, the Hubble Space Telescope observed an enormous white cloud near Saturn's equator which was not present during the Voyager encounters, and, in 1994, another smaller storm was observed. The 1990 storm was an example of a Great White Spot, a unique but short-lived phenomenon which occurs once every Saturnian year, or roughly every 30 Earth years, around the time of the northern hemisphere's summer solstice.[20] Previous Great White Spots were observed in 1876, 1903, 1933, and 1960, with the 1933 storm being the most famous. If the periodicity is maintained, another storm will occur in about 2020.[21] The Hubble Space Telescope (HST) is a telescope in orbit around the Earth, named after astronomer Edwin Hubble. ... The Great White Spot on Saturn, named by analogy from Jupiters Great Red Spot, is a name given to storms that are large enough to be visible by telescope from earth by their characteristic white appearance. ... Illumination of Earth by the sun on the northern hemisphere summer solstice The summer solstice is an astronomical term regarding the position of the sun in relation to the celestial equator. ...


In recent images from the Cassini spacecraft, Saturn's northern hemisphere appears a bright blue, similar to Uranus, as can be seen in the image below. This blue color cannot currently be observed from Earth, because Saturn's rings are currently blocking its northern hemisphere. The color is most likely caused by Rayleigh scattering. Cassini-Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... Rayleigh scattering causing the blue hue of the sky and the reddening at sunset Rayleigh scattering (named after Lord Rayleigh) is the scattering of light, or other electromagnetic radiation, by particles much smaller than the wavelength of the light. ...

Saturn's northern hemisphere, as seen by Cassini. Notice the planet's blue appearance through the ring.
North polar hexagonal cloud feature, discovered by Voyager 1 and confirmed in 2006 by Cassini.
North polar hexagonal cloud feature, discovered by Voyager 1 and confirmed in 2006 by Cassini.[22]

Astronomers using infrared imaging have shown that Saturn has a warm polar vortex and that it is the only such planet known in the solar system. This, they say, is the warmest spot on Saturn. Whereas temperatures on Saturn are normally -185 °C, temperatures on the vortex often reach as high as -122 °C.[23] Image File history File links Size of this preview: 674 × 600 pixelsFull resolution (1010 × 899 pixel, file size: 44 KB, MIME type: image/jpeg)source Mimas and Saturns rings, taken by Cassini. ... Image File history File links Size of this preview: 674 × 600 pixelsFull resolution (1010 × 899 pixel, file size: 44 KB, MIME type: image/jpeg)source Mimas and Saturns rings, taken by Cassini. ... Image File history File links Size of this preview: 688 × 599 pixel Image in higher resolution (15750 × 13717 pixel, file size: 5. ... Image File history File links Size of this preview: 688 × 599 pixel Image in higher resolution (15750 × 13717 pixel, file size: 5. ... For the album by The Verve, see Voyager 1 (album). ... Cassini-Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... For other uses, see Infrared (disambiguation). ... The polar vortex is a persistent, large-scale cyclone located near the Earths poles, in the middle and upper troposphere and the stratosphere. ...


A persisting hexagonal wave pattern around the north polar vortex in the atmosphere at about 78°N was first noted in the Voyager images.[24][25] Unlike the north pole, HST imaging of the south polar region indicates the presence of a jet stream, but no strong polar vortex nor any hexagonal standing wave.[26] However, NASA reported in November 2006 that the Cassini spacecraft observed a 'hurricane-like' storm locked to the south pole that had a clearly defined eyewall.[27] This observation is particularly notable because eyewall clouds had not previously been seen on any planet other than Earth (including a failure to observe an eyewall in the Great Red Spot of Jupiter by the Galileo spacecraft).[28] For other uses, see Hexagon (disambiguation). ... The National Aeronautics and Space Administration (NASA) (IPA [ˈnæsÉ™]) is an agency of the United States government, responsible for the nations public space program. ... This article is about weather phenomena. ... Eye of Typhoon Odessa, Pacific Ocean, August 1985 The eyewall is the region of a tropical cyclone with the strongest winds, the tallest clouds, and the heaviest rain. ... A false-color image of the Great Red Spot of Jupiter from Voyager 1. ... Galileo is prepared for mating with the IUS booster Galileo and Inertial Upper Stage being deployed after being launched by the Space Shuttle Atlantis on the STS-34 mission Galileo was an unmanned spacecraft sent by NASA to study the planet Jupiter and its moons. ...


The straight sides of the northern polar hexagon are each about 13,800 km long. The entire structure rotates with a period of 10h 39 m 24s, the same period as that of the planet's radio emissions, which is assumed to be equal to the period of rotation of Saturn's interior. The hexagonal feature does not shift in longitude like the other clouds in the visible atmosphere.


The pattern's origin is a matter of much speculation. Most astronomers seem to think some sort of standing-wave pattern in the atmosphere; but the hexagon might be a novel sort of aurora. More extreme speculation has Saturn's radio emissions emanating from the hexagon (something we can see and which has the right rotation period) rather than from the planet's interior (something we cannot see).[29] Polygon shapes have been replicated in spinning buckets of fluid in a laboratory.[30]


Magnetic field and magnetosphere

Saturn has an intrinsic magnetic field that has a simple, symmetric shape—a magnetic dipole. Its strength at the equator—0.2 gauss (20 µT)—is approximately one twentieth than that of the field around Jupiter and slightly weaker than Earth's magnetic field.[31] As a result the cronian magnetosphere is much smaller than jovian and extends slightly beyond the orbit of Titan.[32] Most probably, the magnetic field is generated similarly to that of Jupiter—by currents in the metallic-hydrogen layer, which is called a metallic-hydrogen dynamo.[32] Similarly to the those of other planets, this magnetosphere is efficient at deflecting the solar wind particles from the Sun. The moon Titan orbits within the outer part of Saturn's magnetosphere and contributes plasma from the ionized particles in Titan's outer atmosphere.[31] The Earths magnetic field, which is approximately a dipole. ... The gauss, abbreviated as G, is the cgs unit of magnetic flux density (B), named after the German mathematician and physicist Carl Friedrich Gauss. ... The tesla (symbol T) is the SI derived unit of magnetic flux density (or magnetic induction). ... The plasma in the solar wind meeting the heliopause The solar wind is a stream of charged particles (i. ... Sol redirects here. ...


Orbit and rotation

Animation of hexagonal cloud feature.
Animation of hexagonal cloud feature.

The average distance between Saturn and the Sun is over 1,400,000,000 km (9 AU). With an average orbital speed of 9.69 km/s,[3] it takes Saturn 10,759 Earth days (or about 29½ years), to finish one revolution around the Sun.[3] The elliptical orbit of Saturn is inclined 2.48° relative to the orbital plane of the Earth.[3] Because of an eccentricity of 0.056, the distance between Saturn and the Sun varies by approximately 155,000,000 km between perihelion and aphelion,[3] which are the nearest and most distant points of the planet along its orbital path, respectively. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Sol redirects here. ... The astronomical unit (AU or au or a. ... Look up Eccentricity in Wiktionary, the free dictionary. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...


The visible features on Saturn rotate at different rates depending on latitude, and multiple rotation periods have been assigned to various regions (as in Jupiter's case): System I has a period of 10 h 14 min 00 s (844.3°/d) and encompasses the Equatorial Zone, which extends from the northern edge of the South Equatorial Belt to the southern edge of the North Equatorial Belt. All other Saturnian latitudes have been assigned a rotation period of 10 h 39 min 24 s (810.76°/d), which is System II. System III, based on radio emissions from the planet in the period of the Voyager flybys, has a period of 10 h 39 min 22.4 s (810.8°/d); because it is very close to System II, it has largely superseded it.


However, a precise value for the rotation period of the interior remains elusive. While approaching Saturn in 2004, the Cassini spacecraft found that the radio rotation period of Saturn had increased appreciably, to approximately 10 h 45 m 45 s (± 36 s).[33] The cause of the change is unknown—it was thought to be due to a movement of the radio source to a different latitude inside Saturn, with a different rotational period, rather than because of a change in Saturn's rotation.


Later, in March 2007, it was found that the rotation of the radio emissions did not trace the rotation of the planet, but rather is produced by convection of the plasma disc, which is dependent also on other factors besides the planet's rotation. It was reported that the variance in measured rotation periods may be caused by geyser activity on Saturn's moon Enceladus. The water vapor emitted into Saturn's orbit by this activity becomes charged and "weighs down" Saturn's magnetic field, slowing its rotation slightly relative to the rotation of the planet itself. At the time it was stated that there is no currently known method of determining the rotation rate of Saturn's core.[34][35][36] Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ...


The latest estimate of Saturn's rotation based on a compilation of various measurements from the Cassini, Voyager and Pioneer probes was reported in September 2007 is 10 hours, 32 minutes, 35 seconds. [37]


Planetary rings

The rings of Saturn (here: as imaged by Cassini in 2007) are the most spectacular in the Solar System.
The rings of Saturn (here: as imaged by Cassini in 2007) are the most spectacular in the Solar System.[16]
Main article: Rings of Saturn

Saturn is probably best known for its system of planetary rings, which makes it the most visually remarkable object in the solar system.[16] Image File history File links Size of this preview: 800 × 569 pixel Image in higher resolution (4088 × 2908 pixel, file size: 655 KB, MIME type: image/jpeg) Blinding Saturn Taking in the rings in their entirety was the focus of this particular imaging sequence. ... Image File history File links Size of this preview: 800 × 569 pixel Image in higher resolution (4088 × 2908 pixel, file size: 655 KB, MIME type: image/jpeg) Blinding Saturn Taking in the rings in their entirety was the focus of this particular imaging sequence. ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... A planetary ring is a ring of dust and other small particles orbiting around a planet in a flat disc-shaped region. ...


History

The rings were first observed by Galileo Galilei in 1610 with his telescope, but he was unable to identify them as such. He wrote to the Duke of Tuscany that "The planet Saturn is not alone, but is composed of three, which almost touch one another and never move nor change with respect to one another. They are arranged in a line parallel to the zodiac, and the middle one (Saturn itself) is about three times the size of the lateral ones [the edges of the rings]." He also described Saturn as having "ears." In 1612 the plane of the rings was oriented directly at the Earth and the rings appeared to vanish. Mystified, Galileo wondered, "Has Saturn swallowed his children?", referring to the myth of the god Saturn eating his own children to prevent them from overthrowing him.[38] Then, in 1613, they reappeared again, further confusing Galileo.[39] Galileo redirects here. ... This article does not cite any references or sources. ... Cosimo II de Medici, Grand Duke of Tuscany (12 May 1590 – 28 February 1621) ruled as Grand Duke of Tuscany from 1609 to 1621. ... The term zodiac denotes an annual cycle of twelve stations along the ecliptic, the apparent path of the sun across the heavens through the constellations that divide the ecliptic into twelve equal zones of celestial longitude. ...


In 1655, Christiaan Huygens became the first person to suggest that Saturn was surrounded by a ring. Using a telescope that was far superior to those available to Galileo, Huygens observed Saturn and wrote that "It [Saturn] is surrounded by a thin, flat, ring, nowhere touching, inclined to the ecliptic."[39] Christiaan Huygens (pronounced in English (IPA): ; in Dutch: ) (April 14, 1629 – July 8, 1698), was a Dutch mathematician, astronomer and physicist; born in The Hague as the son of Constantijn Huygens. ...


In 1675, Giovanni Domenico Cassini determined that Saturn's ring was composed of multiple smaller rings with gaps between them; the largest of these gaps was later named the Cassini Division. This division in itself is a 4,800 km wide region between the A Ring and B Ring.[40] Giovanni Domenico (Jean-Dominique) Cassini Portrait Giovanni Domenico Cassini (June 8, 1625–September 14, 1712) was an Italian astronomer, engineer, and astrologer. ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ...


In 1859, James Clerk Maxwell demonstrated that the rings could not be solid or they would become unstable and break apart. He proposed that the rings must be composed of numerous small particles, all independently orbiting Saturn.[41] Maxwell's theory was proven correct in 1895 through spectroscopic studies of the rings carried out by James Keeler of Lick Observatory. James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and theoretical physicist from Edinburgh, Scotland, UK. His most significant achievement was aggregating a set of equations in electricity, magnetism and inductance — eponymously named Maxwells equations — including an important modification (extension) of the Ampères... James Edward Keeler (September 10, 1857 – August 12, 1900) was an American astronomer. ... The Lick Observatory is an astronomical observatory, owned and operated by the University of California. ...


Physical characteristics

Saturn's rings cut across an eerie scene that is ruled by Titan's luminous crescent and globe-encircling haze, broken by the small moon Enceladus, whose cryovolcanos are dimly visible at its south pole. North is up. Imaged by Cassini in 2006.
Saturn's rings cut across an eerie scene that is ruled by Titan's luminous crescent and globe-encircling haze, broken by the small moon Enceladus, whose cryovolcanos are dimly visible at its south pole. North is up. Imaged by Cassini in 2006.

The rings can be viewed using a quite modest modern telescope or with good binoculars. They extend from 6,630 km to 120,700 km above Saturn's equator, average approximately one kilometer in thickness, and are composed of 93 percent water ice with a smattering of tholin impurities, and 7 percent amorphous carbon.[42] They range in size from specks of dust to the size of a small automobile.[43] There are two main theories regarding the origin of Saturn's rings. One theory, originally proposed by Édouard Roche in the 19th century, is that the rings were once a moon of Saturn whose orbit decayed until it came close enough to be ripped apart by tidal forces (see Roche limit). A variation of this theory is that the moon disintegrated after being struck by a large comet or asteroid. The second theory is that the rings were never part of a moon, but are instead left over from the original nebular material from which Saturn formed. This theory is not widely accepted today, since Saturn's rings are thought to be unstable over periods of millions of years and therefore of relatively recent origin. Image File history File links Download high-resolution version (890x524, 13 KB) Other versions http://photojournal. ... Image File history File links Download high-resolution version (890x524, 13 KB) Other versions http://photojournal. ... Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ... Ganesa Macula, a dark feature on Saturns moon Titan, might be a cryovolcanic dome. ... Porro-prism binoculars with central focusing Binocular telescopes, or binoculars, (also known as field glasses) are two identical or mirror-symmetrical telescopes mounted side-by-side and aligned to point accurately in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects. ... This article is about water ice. ... Tholin is a heteropolymer formed by solar ultraviolet irradiation of simple organic compounds such as methane or ethane. ... For other uses, see Carbon (disambiguation). ... Édouard Albert Roche (1820-1883) was a French scientist. ... Comet Shoemaker-Levy 9 after breaking up under the influence of Jupiters tidal forces. ... The Roche limit, sometimes referred to as the Roche radius, is the distance within which a celestial body held together only by its own gravity will disintegrate due to a second celestial bodys tidal forces exceeding the first bodys gravitational self-attraction. ... Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ... For other uses, see Asteroid (disambiguation). ... The Triangulum Emission Nebula NGC 604 The Pillars of Creation from the Eagle Nebula For other uses, see Nebula (disambiguation). ...


While the largest gaps in the rings, such as the Cassini Division and Encke Division, can be seen from Earth, the Voyager spacecrafts discovered the rings to have an intricate structure of thousands of thin gaps and ringlets. This structure is thought to arise from the gravitational pull of Saturn's many moons in several different ways. Some gaps are cleared out by the passage of tiny moonlets such as Pan, many more of which may yet be discovered, and some ringlets seem to be maintained by the gravitational effects of small shepherd satellites such as Prometheus and Pandora. Other gaps arise from resonances between the orbital period of particles in the gap and that of a more massive moon further out; Mimas maintains the Cassini division in this manner. Still more structure in the rings consists of spiral waves raised by the moons' periodic gravitational perturbations. The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... Atmosphere none Pan (pan, Greek Πάν) is a moon of Saturn, named after the god Pan. ... A planetary ring is a ring of dust and other small particles orbiting around a planet in a flat disc-shaped region. ... Prometheus (proe-mee-thee-us, Greek Προμηθέας) is a moon of Saturn. ... Pandora (pan-dor-a, Greek Πανδώρα) is a moon of Saturn. ... In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other. ... Mimas (mee-məs or mye-məs, IPA: , Greek Μίμᾱς, rarely Μίμανς) is a moon of Saturn that was discovered in 1789 by William Herschel. ...


Data from the Cassini space probe indicate that the rings of Saturn possess their own atmosphere, independent of that of the planet itself. The atmosphere is composed of molecular oxygen gas (O2) produced when ultraviolet light from the Sun disintegrates water ice in the rings. Chemical reactions between water molecule fragments and further ultraviolet stimulation create and eject, among other things O2. According to models of this atmosphere, H2 is also present. The O2 and H2 atmospheres are so sparse that if the entire atmosphere were somehow condensed onto the rings, it would be on the order of one atom thick.[44] The rings also have a similarly sparse OH (hydroxide) atmosphere. Like the O2, this atmosphere is produced by the disintegration of water molecules, though in this case the disintegration is done by energetic ions that bombard water molecules ejected by Saturn's moon Enceladus. This atmosphere, despite being extremely sparse, was detected from Earth by the Hubble Space Telescope.[45] General Name, symbol, number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, period, block 16, 2, p Appearance colorless (gas) pale blue (liquid) Standard atomic weight 15. ... For other uses, see Ultraviolet (disambiguation). ... This article is about the electrically charged particle. ... Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ...


Saturn shows complex patterns in its brightness.[8] Most of the variability is due to the changing aspect of the rings,[46] [47] and this goes through two cycles every orbit. However, superimposed on this is variability due to the eccentricity of the planet's orbit that causes the planet to display brighter oppositions in the northern hemisphere than it does in the southern.[48]


In 1980, Voyager I made a fly-by of Saturn that showed the F-ring to be composed of three narrow rings that appeared to be braided in a complex structure; it is now known that the outer two rings consist of knobs, kinks and lumps that give the illusion of braiding, with the less bright third ring lying inside them.


Spokes of the rings

Spokes in the B ring, imaged by Voyager 2 in 1981
Spokes in the B ring, imaged by Voyager 2 in 1981

Until 1980, the structure of the rings of Saturn was explained exclusively as the action of gravitational forces. The Voyager spacecraft found radial features in the B ring, called spokes, which could not be explained in this manner, as their persistence and rotation around the rings were not consistent with orbital mechanics.[49]The spokes appear dark against the lit side of the rings, and light when seen against the unlit side. It is assumed that they are microscopic dust particles that have levitated away from the ring plane and that they are connected to electromagnetic interactions, as they rotate almost synchronously with the magnetosphere of Saturn. However, the precise mechanism generating the spokes is still unknown.[50] Image:Voyager ring spokes. ... Image:Voyager ring spokes. ... Trajectory Voyager 2 is an unmanned interplanetary spacecraft, launched on August 20, 1977. ... Gravity redirects here. ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... This article or section should be merged with Celestial Mechanics Astrodynamics is the study and creation of orbits, especially those of artificial satellites. ... Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge, and is in turn affected by the presence and motion of those particles. ... A magnetosphere is the region around an astronomical object in which phenomena are dominated or organized by its magnetic field. ...

These are three images of the spokes imaged by Cassini in 2005.

Twenty-five years later, the spokes were observed again, this time by Cassini. They appear to be a seasonal phenomenon, disappearing in the Saturnian midwinter/midsummer and reappearing as Saturn comes closer to equinox. The spokes were not visible when Cassini arrived at Saturn in early 2004. Some scientists speculated that the spokes would not be visible again until 2007, based on models attempting to describe spoke formation. Nevertheless, the Cassini imaging team kept looking for spokes in images of the rings, and the spokes reappeared in images taken on September 5, 2005.[51] Image File history File links Size of this preview: 800 × 205 pixelsFull resolution (1000 × 256 pixel, file size: 54 KB, MIME type: image/jpeg) Saturn Ring Spokes captured by Cassini on Sept. ... Image File history File links Size of this preview: 800 × 205 pixelsFull resolution (1000 × 256 pixel, file size: 54 KB, MIME type: image/jpeg) Saturn Ring Spokes captured by Cassini on Sept. ... Cassini-Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... For other uses, see Equinox (disambiguation). ... is the 248th day of the year (249th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ...


Natural satellites

Four of Saturn's moons: Dione, Titan, Prometheus (edge of rings), Telesto (top center)
Four of Saturn's moons: Dione, Titan, Prometheus (edge of rings), Telesto (top center)

Saturn has a large number of moons. The precise figure is uncertain, as the orbiting chunks of ice in Saturn's rings are all technically moons, and it is difficult to draw a distinction between a large ring particle and a tiny moon. As of 2007, a total of 60 individual moons have been identified, plus 3 unconfirmed moons that could be small dust clumps in the rings. Out of those, 48 have been named. Many of the moons are very small: out of 60, 34 are less than 10 km in diameter, and another 13 less than 50 km.[52] Only seven of them are massive enough to have collapsed into spheroids under their own gravitation. These are compared with Earth's moon in the table below. The Saturnian system (photographic montage) Saturn has 60 confirmed natural satellites, plus three hypothetical moons. ... Image File history File links Download high resolution version (962x877, 30 KB) Summary Original Caption Released with Image: In a rare moment, the Cassini spacecraft captured this enduring portrait of a near-alignment of four of Saturns restless moons. ... Image File history File links Download high resolution version (962x877, 30 KB) Summary Original Caption Released with Image: In a rare moment, the Cassini spacecraft captured this enduring portrait of a near-alignment of four of Saturns restless moons. ... Atmosphere none Dione (dye-oe-nee, Greek Διώνη) is a moon of Saturn discovered by Giovanni Cassini in 1684. ... Prometheus (proe-mee-thee-us, Greek Προμηθέας) is a moon of Saturn. ... Atmosphere none Telesto IPA: , Greek Τελεστώ) is a moon of Saturn. ... A natural satellite is an object that orbits a planet or other body larger than itself and which is not man-made. ...


Titan, Saturn's largest moon, is the only moon in the Solar System to have a dense atmosphere. While most of the moons in the Saturnian system are small in size, Titan is, relatively speaking, gigantic. After the Sun, the eight planets and Jupiter's moon Ganymede, Titan is the most massive object in the Solar System.[10] Titan comprises more than 90 percent of the mass in orbit around Saturn, including the rings, and the other moons range from one hundredth to one hundred millionth its mass.[53]


Traditionally, most of Saturn's other moons are named after Titans of Greek mythology. This started because John Herschel—son of William Herschel, discoverer of Mimas and Enceladus—suggested doing so in his 1847 publication Results of Astronomical Observations made at the Cape of Good Hope,[54] because they were the sisters and brothers of Cronos (the Greek Saturn). This article is about the race of Titans in Greek mythology. ... John Herschel Sir John Frederick William Herschel (7 March 1792 – 11 May 1871) was an English mathematician and astronomer. ... For other persons named William Herschel, see William Herschel (disambiguation). ... Cronus is not to be confused with Chronos, the personification of time. ...



Saturn's major satellites, compared with Earth's Moon.
Name

(Pronunciation key) This article is about Earths moon. ...

Diameter
(km)
Mass
(kg)
Orbital radius (km) Orbital period (days)
Mimas ˈmaɪməs 400
(10% Luna)
0.4×1020
(0.05% Luna)
185,000
(50% Luna)
0.9
(3% Luna)
Enceladus ɛnˈsɛlədəs 500
(15% Luna)
1.1×1020
(0.2% Luna)
238,000
(60% Luna)
1.4
(5% Luna)
Tethys ˈtiːθɨs 1060
(30% Luna)
6.2×1020
(0.8% Luna)
295,000
(80% Luna)
1.9
(7% Luna)
Dione daɪˈoʊni 1120
(30% Luna)
11×1020
(1.5% Luna)
377,000
(100% Luna)
2.7
(10% Luna)
Rhea ˈriːə 1530
(45% Luna)
23×1020
(3% Luna)
527,000
(140% Luna)
4.5
(20% Luna)
Titan ˈtaɪtən 5150
(150% Luna)
1350×1020
(180% Luna)
1,222,000
(320% Luna)
16
(60% Luna)
Iapetus aɪˈæpɨtəs 1440
(40% Luna)
20×1020
(3% Luna)
3,560,000
(930% Luna)
79
(290% Luna)
For a timeline of discovery dates, see Timeline of discovery of Solar System planets and their natural satellites.

Mimas (mee-məs or mye-məs, IPA: , Greek Μίμᾱς, rarely Μίμανς) is a moon of Saturn that was discovered in 1789 by William Herschel. ... Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ... Atmosphere none Tethys (tee-thəs or teth-əs, IPA , Greek Τηθύς) is a moon of Saturn that was discovered by Giovanni Domenico Cassini in 1684. ... Atmosphere none Dione (dye-oe-nee, Greek Διώνη) is a moon of Saturn discovered by Giovanni Cassini in 1684. ... Atmosphere none Rhea (ree-a, Greek ‘Ρέα) is the second largest moon of Saturn and was discovered in 1672 by Giovanni Domenico Cassini. ... Titan (, from Ancient Greek Τῑτάν) or Saturn VI is the largest moon of Saturn and the only moon known to have a dense atmosphere. ... Iapetus (eye-ap-ə-təs, IPA , Greek Ιαπετός) is the third-largest moon of Saturn, discovered by Giovanni Domenico Cassini in 1671. ... This timeline of discovery of Solar System planets and their natural satellites charts the progress of the discovery of new bodies over history. ...

History and exploration

Main article: Exploration of Saturn
A Hubble Space Telescope image, captured in October 1996, shows Saturn's rings from just past edge-on. Credit: NASA/ESA.

The exploration of Saturn has been soley through unmanned spacecraft. ... Image File history File links Saturns_rings. ... Image File history File links Saturns_rings. ... The National Aeronautics and Space Administration (NASA) (IPA [ˈnæsə]) is an agency of the United States government, responsible for the nations public space program. ... ESA redirects here. ...

Ancient times and observation

See also: Planet#Etymology

Saturn has been known since prehistoric times.[55] In ancient times, it was the most distant of the five known planets in the solar system (excluding Earth) and thus a major character in various mythologies. In ancient Roman mythology, the god Saturnus, from which the planet takes its name, was the god of the agricultural and harvest sector.[56] The Romans considered Saturnus the equivalent of the Greek god Kronos.[56] The Greeks had made the outermost planet sacred to Kronos,[57] and the Romans followed suit. This article is about the astronomical term. ... A head of Minerva found in the ruins of the Roman baths in Bath Roman mythology, the mythological beliefs of the people of Ancient Rome, can be considered as having two parts. ... Saturnus, Caravaggio, 16th c. ... The bust of Zeus found at Otricoli (Sala Rotonda, Museo Pio-Clementino, Vatican) Greek mythology is the body of stories belonging to the Ancient Greeks concerning their gods and heroes, the nature of the world and the origins and significance of their own cult and ritual practices. ... Chronos is the personification of time in Greek mythology There is also Cronus, the similarly named Greek mythological Titan, father of Zeus. ...


In Hindu astrology, there are nine astrological objects, known as Navagrahas. Saturn, one of them, is known as "Sani" or "Shani," the Judge among all the planets, and determines everyone according to their own performed deeds bad or good.[56] Ancient Chinese and Japanese culture designated the planet Saturn as the earth star (土星). This was based on Five Elements which were traditionally used to classify natural elements. In ancient Hebrew, Saturn is called 'Shabbathai'. Its angel is Cassiel. Its intelligence, or beneficial spirit, is Agiel (layga), and its spirit (darker aspect) is Zazel (lzaz). In Ottoman Turkish and in Malay, its name is 'Zuhal', derived from Arabic زحل. Jyotisha (, in Hindi and English usage Jyotish; sometimes called Hindu astrology, Indian astrology, and/or Vedic astrology) is the Hindu system of astrology, one of the six disciplines of Vedanga, and regarded as one of the oldest schools of ancient astrology to have had an independent origin, affecting all other... In Hindu astrology, the Navagraha are the nine chief celestial beings: Surya (Sun) Chandra (Moon) Chevaai (Mars) Budhan (Mercury) Guru (Jupiter) Shukran (Venus) Shani (Saturn) Rahu (Head of Demon Snake) Ketu (Tail of Demon Snake). ... Shani (also spelled Åšani)(Sanskrit: शनि) is one of the Navagraha which are the nine primary celestial beings in Hindu astrology (that is, Vedic astrology), Shani is embodied in the planet Saturn. ... Chinese Wood (木) | Fire (火) Earth (土) | Metal (金) | Water (æ°´) Japanese Earth (地) | Water (æ°´) | Fire (火) | Air / Wind (風) | Void / Sky / Heaven (空) Hinduism and Buddhism Vayu / Pavan — Air / Wind Agni / Tejas — Fire Akasha — Aether Prithvi / Bhumi — Earth Ap / Jala — Water In traditional Chinese philosophy, natural phenomena can be classified into the Five Elements (Chinese: ; Pinyin: ): wood, fire... Hebrew redirects here. ... Cassiel, (Hebrew קפציאל Kafziel) is the latin name of an angel in post-biblical Judeo-Christian mythology, particularly that of the Kabbalah. ... Agiel (Hebrew Word: אגיאל) The Intelligence (beneficial spirit) of Saturn. ... Ottoman Turkish is the variant of the Turkish language which was used as the administrative and literary language of the Ottoman Empire, containing extensive borrowings from Arabic and Persian and written in Arabic script. ... Not to be confused with the Malayalam language, spoken in India. ... Arabic redirects here. ...


Saturn's rings require at least a 75 mm diameter telescope to resolve and thus were not known to exist until Galileo first saw them in 1610.[58] He, though, thought of them as two moons on Saturn's sides. It was not until Christian Huygens used greater telescopic magnification that the rings were assumed to be rings. Huygens also discovered Saturn's moon Titan. Some time later, Jean-Dominique Cassini discovered four other moons: Iapetus, Rhea, Tethys, and Dione. In 1675, Cassini also discovered the gap now known as the Cassini Division.[59] This article does not cite any references or sources. ... Galileo can refer to: Galileo Galilei, astronomer, philosopher, and physicist (1564 - 1642) the Galileo spacecraft, a NASA space probe that visited Jupiter and its moons the Galileo positioning system Life of Galileo, a play by Bertolt Brecht Galileo (1975) - screen adaptation of the play Life of Galileo by Bertolt Brecht... Christiaan Huygens Christiaan Huygens (approximate pronunciation: HOW-khens; SAMPA /h9yGEns/ or /h@YG@ns/) (April 14, 1629–July 8, 1695), was a Dutch mathematician and physicist; born in The Hague as the son of Constantijn Huygens. ... Giovanni Domenico (Jean-Dominique) Cassini Giovanni Domenico Cassini (June 8, 1625 - September 14, 1712) was an Italian-French astronomer and engineer. ... Iapetus (eye-ap-É™-tÉ™s, IPA , Greek Ιαπετός) is the third-largest moon of Saturn, discovered by Giovanni Domenico Cassini in 1671. ... Atmosphere none Rhea (ree-a, Greek ‘Ρέα) is the second largest moon of Saturn and was discovered in 1672 by Giovanni Domenico Cassini. ... Atmosphere none Tethys (tee-thÉ™s or teth-É™s, IPA , Greek Τηθύς) is a moon of Saturn that was discovered by Giovanni Domenico Cassini in 1684. ... Atmosphere none Dione (dye-oe-nee, Greek Διώνη) is a moon of Saturn discovered by Giovanni Cassini in 1684. ...


No further discoveries of significance were made until 1789 when William Herschel discovered two further moons, Mimas and Enceladus. The irregularly shaped satellite Hyperion, which has a resonance with Titan, was discovered in 1848 by a British team. For other persons named William Herschel, see William Herschel (disambiguation). ... Mimas (mee-məs or mye-məs, IPA: , Greek Μίμᾱς, rarely Μίμανς) is a moon of Saturn that was discovered in 1789 by William Herschel. ... Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ... Hyperion (IPA: , Greek Ὑπερίων) is a moon of Saturn discovered by William Cranch Bond, George Phillips Bond and William Lassell in 1848. ... In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other. ...


In 1899 William Henry Pickering discovered Phoebe, a highly irregular satellite that does not rotate synchronously with Saturn as the larger moons do. Phoebe was the first such satellite found, and it takes more than a year to orbit Saturn in a retrograde orbit. During the early twentieth century, research on Titan led to the confirmation in 1944 that it had a thick atmosphere - a feature unique among the solar system's moons. William Henry Pickering (February 15, 1858 – January 17, 1938) was an American astronomer, brother of Edward Charles Pickering. ... For other meanings see Phoebe. ... In astronomy, an irregular satellite is a natural satellite following a distant, inclined, often retrograde orbit and believed to be captured as opposed to a regular satellite, formed in situ. ... This article is about retrograde motion. ...


Pioneer 11 flyby

Saturn was first visited by Pioneer 11 on September 1979. It flew within 20,000 km of the planet's cloud tops. Low resolution images were acquired of the planet and a few of its moons; the resolution of the images was not good enough to discern surface features. The spacecraft also studied the rings; among the discoveries were the thin F-ring and the fact that dark gaps in the rings are bright when viewed towards the Sun, or in other words, they are not empty of material. Pioneer 11 also measured the temperature of Titan.[60] Position of Pioneer 10 and 11 Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ...


Voyager flybys

In November 1980, the Voyager 1 probe visited the Saturn system. It sent back the first high-resolution images of the planet, rings, and satellites. Surface features of various moons were seen for the first time. Voyager 1 performed a close flyby of Titan, greatly increasing our knowledge of the atmosphere of the moon. However, it also proved that Titan's atmosphere is impenetrable in visible wavelengths; so, no surface details were seen. The flyby also changed the spacecraft's trajectory out from the plane of the solar system.[61] For the album by The Verve, see Voyager 1 (album). ...


Almost a year later, in August 1981, Voyager 2 continued the study of the Saturn system. More close-up images of Saturn's moons were acquired, as well as evidence of changes in the atmosphere and the rings. Unfortunately, during the flyby, the probe's turnable camera platform stuck for a couple of days, and some planned imaging was lost. Saturn's gravity was used to direct the spacecraft's trajectory towards Uranus.[61] Trajectory Voyager 2 is an unmanned interplanetary spacecraft, launched on August 20, 1977. ...


The probes discovered and confirmed several new satellites orbiting near or within the planet's rings. They also discovered the small Maxwell gap (a gap within the C Ring) and Keeler gap (a 42 km wide gap in the A Ring). The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ...


Cassini orbiter

Saturn eclipses the Sun, as seen from Cassini.
Saturn eclipses the Sun, as seen from Cassini.

On July 1, 2004, the Cassini–Huygens spacecraft performed the SOI (Saturn Orbit Insertion) maneuver and entered into orbit around Saturn. Before the SOI, Cassini had already studied the system extensively. In June 2004, it had conducted a close flyby of Phoebe, sending back high-resolution images and data. Image File history File links Download high-resolution version (2766x1364, 296 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Saturn Portal:Astronomy/Picture User talk:Titoxd User:Istvan Wikipedia:Featured pictures/Sciences/Astronomy Wikipedia:Featured pictures thumbs... Image File history File links Download high-resolution version (2766x1364, 296 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Saturn Portal:Astronomy/Picture User talk:Titoxd User:Istvan Wikipedia:Featured pictures/Sciences/Astronomy Wikipedia:Featured pictures thumbs... is the 182nd day of the year (183rd in leap years) in the Gregorian calendar. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... Cassini–Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... For other meanings see Phoebe. ...


Cassini's flyby of Saturn's largest moon, Titan, has captured radar images of large lakes and their coastlines with numerous islands and mountains. The orbiter completed two Titan flybys before releasing the Huygens probe on December 25, 2004. Huygens descended onto the surface of Titan on January 14, 2005, sending a flood of data during the atmospheric descent and after the landing. During 2005, Cassini conducted multiple flybys of Titan and icy satellites. Cassini's last Titan flyby was scheduled for July 19, 2007. This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... The Huygens probe, supplied by the European Space Agency (ESA) and named after the Dutch 17th century astronomer Christiaan Huygens, is an atmospheric entry probe carried to Saturns moon Titan as part of the Cassini-Huygens mission. ... is the 359th day of the year (360th in leap years) in the Gregorian calendar. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... is the 14th day of the year in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... is the 200th day of the year (201st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ...


Since early 2005, scientists have been tracking lightning on Saturn, primarily found by Cassini. The power of the lightning is said to be approximately 1000 times than that of the lightning on Earth. In addition, scientists believe that this storm is the strongest of its kind ever seen.[62]


On March 10, 2006, NASA reported that, through images, the Cassini probe found evidence of liquid water reservoirs that erupt in geysers on Saturn's moon Enceladus. Images had also shown particles of water in its liquid state being emitted by icy jets and towering plumes. According to Dr. Andrew Ingersoll, California Institute of Technology, "Other moons in the solar system have liquid-water oceans covered by kilometers of icy crust. What's different here is that pockets of liquid water may be no more than tens of meters below the surface."[63] March 10 is the 69th day of the year (70th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Strokkur geyser, Iceland A geyser is a type of hot spring that erupts periodically, ejecting a column of hot water and steam into the air. ... Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ...


On September 20, 2006, a Cassini probe photograph revealed a previously undiscovered planetary ring, outside the brighter main rings of Saturn and inside the G and E rings. Apparently, the source of this ring is the result of the crashing of a meteoroid off two of the moons of Saturn. [64] is the 263rd day of the year (264th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...


In July 2006, Cassini saw the first proof of hydrocarbon lakes near Titan's north pole, which was confirmed in January 2007. In March 2007, additional images near Titan's north pole discovered hydrocarbon "seas," the largest of which is almost the size of the Caspian Sea.[65] The Caspian Sea is the largest enclosed body of water on Earth by area, variously classed as the worlds largest lake or a full-fledged sea. ...


In October 2006, the probe detected a 5,000 km diameter hurricane with an eyewall at Saturn's South Pole.[66]


As of 2006, the probe has discovered and confirmed 4 new satellites. Its primary mission will end in 2008 when the spacecraft will be expected to have completed 74 orbits around the planet. The probe, however, is expected to have at least one mission extension. 2006 is a common year starting on Sunday of the Gregorian calendar. ...


Best viewing

Saturn Oppositions: 2001–2029

Saturn is the most distant of the five planets easily visible to the naked eye, the other four being Mercury, Venus, Mars, and Jupiter (Uranus and occasionally 4 Vesta are visible to the naked eye in very dark skies), and was the last planet known to early astronomers until Uranus was discovered in 1781. Saturn appears to the naked eye in the night sky as a bright, yellowish star varying usually between magnitude +1 and 0 and takes approximately 29½ years to make a complete circuit of the ecliptic against the background constellations of the zodiac. Optical aid (large binoculars or a telescope) magnifying at least 20X is required to clearly resolve Saturn's rings for most people.[16] Download high resolution version (642x737, 97 KB)These views demonstrate the 29 year period for oppositions of Saturn and the dramatic changes in the appearance of the rings. ... Download high resolution version (642x737, 97 KB)These views demonstrate the 29 year period for oppositions of Saturn and the dramatic changes in the appearance of the rings. ... [[Link titleBold text // ]] This article is about the planet. ... For other uses, see Venus (disambiguation). ... Adjectives: Martian Atmosphere Surface pressure: 0. ... 4 Vesta (ves-ta) is the second most massive asteroid in the asteroid belt, with a mean diameter of about 530 km and an estimated mass 12% the mass of the entire asteroid belt. ... The plane of the ecliptic is well seen in this picture from the 1994 lunar prospecting Clementine spacecraft. ... The term zodiac denotes an annual cycle of twelve stations along the ecliptic, the apparent path of the sun across the heavens through the constellations that divide the ecliptic into twelve equal zones of celestial longitude. ...


While it is a rewarding target for observation for most of the time it is visible in the sky, Saturn and its rings are best seen when the planet is at or near opposition (the configuration of a planet when it is at an elongation of 180° and thus appears opposite the Sun in the sky). During the opposition of December 17, 2002, Saturn appeared at its brightest due to a favorable orientation of the rings relative to the Earth.[47]
Opposition is a term used in positional astronomy and astrology to indicate when one celestial body is on the opposite side of the sky when viewed from a particular place (usually the Earth). ... This diagram shows the elongations (or angle) of the Earths position from the Sun. ... December 17 is the 351st day of the year (352nd in leap years) in the Gregorian calendar. ... Also see: 2002 (number). ... This article is about Earth as a planet. ...


See also

Solar System Portal

Image File history File links Download high resolution version (1024x1274, 113 KB) Original caption released with image This is a montage of planetary images taken by spacecraft managed by the Jet Propulsion Laboratory in Pasadena, CA. Included are (from top to bottom) images of Mercury, Venus, Earth (and Moon), Mars... Planets in astrology have a different meaning to the modern astronomical understanding of what a planet is. ... The planet Saturn is featured in numerous science fiction novels and films, although the planet itself usually serves more as a pretty backdrop than as the actual setting. ... Dragon Storm Dragon Storm (dubbed so in September 2004 because of its unusual shape) is a name given to a large, bright and complex storm in Saturns southern hemisphere. ...

References

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  2. ^ Orbital elements refer to the barycenter of the Saturn system, and are the instantaneous osculating values at the precise J2000 epoch. Barycenter quantities are given because, in contrast to the planetary centre, they do not experience appreciable changes on a day-to-day basis from to the motion of the moons.
  3. ^ a b c d e f g h i j k l m n o p q r s Williams, Dr. David R. (September 07, 2006). Saturn Fact Sheet. NASA. Retrieved on 2007-07-31.
  4. ^ a b c d Seidelmann, P. Kenneth; Archinal, B. A.; A’hearn, M. F.; et.al. (2007). "Report of the IAU/IAGWorking Group on cartographic coordinates and rotational elements: 2006". Celestial Mech. Dyn. Astr. 90: 155–180. doi:10.1007/s10569-007-9072-y. 
  5. ^ a b c d e f g h Refers to the level of 1 bar atmospheric pressure
  6. ^ NASA: Solar System Exploration: Planets: Saturn: Facts & Figures
  7. ^ Than, Ker (September 06, 2007). Length of Saturn's Day Revised. Space.com. Retrieved on 2007-09-06.
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  46. ^ Schmude, Richard, Jr. (September 22, 2006). Wideband photometric magnitude measurements of Saturn made during the 2005-06 Apparition. Georgia Journal of Science. Retrieved on 2007-10-14.
  47. ^ a b Schmude, Richard W Jr (2003). SATURN IN 2002-03. Georgia Journal of Science. Retrieved on 2007-10-14.
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  • Lovett, L.; Horvath, J.; Cuzzi, J. (2006). Saturn: A New View. New York: Harry N. Abrams, Inc.. ISBN 0810930900. 
  • Karttunen, H.; Kröger, P.; et al. (2007). Fundamental Astronomy. New York: Springer, 5th edition. ISBN 3540341439. 

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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 119th day of the year (120th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 117th day of the year (118th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 187th day of the year (188th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 120th day of the year (121st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 208th day of the year (209th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 208th day of the year (209th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 205th day of the year (206th in leap years) in the Gregorian calendar. ... Sir Patrick Moore presenting The Sky at Night, October 2005 Sir Alfred Patrick Caldwell-Moore, CBE, HonFRS, FRAS (born 4 March 1923), known as Patrick Moore, is an English amateur astronomer who has attained legendary status in British astronomy as a writer and television presenter of the subject and who... 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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 211th day of the year (212th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 187th day of the year (188th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 143rd day of the year (144th in leap years) in the Gregorian calendar. ... The National Aeronautics and Space Administration (NASA) (IPA [ˈnæsə]) is an agency of the United States government, responsible for the nations public space program. ... 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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 196th day of the year (197th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 81st day of the year (82nd in leap years) in the Gregorian calendar. ... For information on Wikipedia press releases, see Wikipedia:Press releases. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 81st day of the year (82nd in leap years) in the Gregorian calendar. ... Science is the journal of the American Association for the Advancement of Science (AAAS). ... 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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 187th day of the year (188th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 189th day of the year (190th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 209th day of the year (210th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 206th day of the year (207th in leap years) in the Gregorian calendar. ... For other uses, see BBC (disambiguation). ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 187th day of the year (188th in leap years) in the Gregorian calendar. ... The American Astronomical Society (AAS) is a US society of professional astronomers and other interested individuals, headquartered in Washington, DC. The main aim of the AAS is provide a political voice for its members and organise their lobbying. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 188th day of the year (189th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 287th day of the year (288th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 287th day of the year (288th in leap years) in the Gregorian calendar. ... The British Astronomical Association, BAA, is the main national association of amateur astronomers in the UK. It was founded in London in 1890. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 188th day of the year (189th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 205th day of the year (206th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 206th day of the year (207th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... is the 258th day of the year (259th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 187th day of the year (188th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 143rd day of the year (144th in leap years) in the Gregorian calendar. ... is the 14th day of the year in the Gregorian calendar. ... 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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 208th day of the year (209th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 189th day of the year (190th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 189th day of the year (190th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 269th day of the year (270th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 193rd day of the year (194th in leap years) in the Gregorian calendar. ...

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See also astronomical objects, the solar system's list of objects, sorted by radius or mass, and the Solar System Portal

Image File history File links Commons-logo. ... Wikipedia does not have an article with this exact name. ... Image File history File links Wikibooks-logo. ... Image File history File links Wikiquote-logo. ... Image File history File links Wikisource-logo. ... Image File history File links Commons-logo. ... Image File history File links WikiNews-Logo. ... Image File history File links Wikiversity-logo-Snorky. ... The Saturnian system (photographic montage) Saturn has 60 confirmed natural satellites, plus three hypothetical moons. ... Mimas (mee-mÉ™s or mye-mÉ™s, IPA: , Greek Μίμᾱς, rarely Μίμανς) is a moon of Saturn that was discovered in 1789 by William Herschel. ... Atmosphere Surface pressure: trace, significant spatial variability[8][9] Composition: 91% Water vapour 4% Nitrogen 3. ... Atmosphere none Tethys (tee-thÉ™s or teth-É™s, IPA , Greek Τηθύς) is a moon of Saturn that was discovered by Giovanni Domenico Cassini in 1684. ... Atmosphere none Dione (dye-oe-nee, Greek Διώνη) is a moon of Saturn discovered by Giovanni Cassini in 1684. ... Atmosphere none Rhea (ree-a, Greek ‘Ρέα) is the second largest moon of Saturn and was discovered in 1672 by Giovanni Domenico Cassini. ... Titan (, from Ancient Greek Τῑτάν) or Saturn VI is the largest moon of Saturn and the only moon known to have a dense atmosphere. ... Hyperion (IPA: , Greek Ὑπερίων) is a moon of Saturn discovered by William Cranch Bond, George Phillips Bond and William Lassell in 1848. ... Iapetus (eye-ap-É™-tÉ™s, IPA , Greek Ιαπετός) is the third-largest moon of Saturn, discovered by Giovanni Domenico Cassini in 1671. ... Download high resolution version (650x813, 21 KB)Original Caption Released with Image: This true color picture was assembled from Voyager 2 Saturn images obtained Aug. ... Dragon Storm Dragon Storm (dubbed so in September 2004 because of its unusual shape) is a name given to a large, bright and complex storm in Saturns southern hemisphere. ... The Great White Spot on Saturn, named by analogy from Jupiters Great Red Spot, is a name given to storms that are large enough to be visible by telescope from earth by their characteristic white appearance. ... The full set of rings, photographed as Saturn eclipsed the sun from the vantage of the Cassini spacecraft on September 15, 2006 (brightness has been exaggerated in this image). ... The Saturnian system (photographic montage) Moons of Saturn (photographic montage) Saturn has 60 confirmed natural satellites, plus three hypothetical moons. ... The exploration of Saturn has been soley through unmanned spacecraft. ... Position of Pioneer 10 and 11 Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ... Voyager Project redirects here. ... Cassini–Huygens is a joint NASA/ESA/ASI unmanned space mission intended to study Saturn and its moons. ... A Saturn-crosser asteroid is an asteroid whose orbit crosses that of Saturn. ... Delta Octantis has the distinction of being Saturns southern pole star. ... Saturn kilometric radiation is the name given to intense radio emissions coming from Saturn. ... The planet Saturn is featured in numerous science fiction novels and films, although the planet itself usually serves more as a pretty backdrop than as the actual setting. ... This article is about the Solar System. ... Sol redirects here. ... [[Link titleBold text // ]] This article is about the planet. ... For other uses, see Venus (disambiguation). ... This article is about Earth as a planet. ... Adjectives: Martian Atmosphere Surface pressure: 0. ... Spectral type: G[8] Absolute magnitude: 3. ... For other uses, see Jupiter (disambiguation). ... For other uses, see Uranus (disambiguation). ... For other uses, see Neptune (disambiguation). ... For other uses, see Pluto (disambiguation). ... Absolute magnitude: −1. ... This article is about the astronomical term. ... Artists impression of Pluto (background) and Charon (foreground). ... A natural satellite is an object that orbits a planet or other body larger than itself and which is not man-made. ... This article is about Earths moon. ... The relative sizes of and distance between Mars, Phobos, and Deimos, to scale : Phobos (top) and Deimos (bottom). ... Jupiters 4 Galilean moons, in a composite image comparing their sizes and the size of Jupiter (Great Red Spot visible). ... The Saturnian system (photographic montage) Moons of Saturn (photographic montage) Saturn has 60 confirmed natural satellites, plus three hypothetical moons. ... Uranus has twenty-seven known moons. ... Neptune (top) and Triton (bottom), 3 days after the Voyager 2 flyby. ... Hubble image of the Plutonian system Pluto has three known moons. ... Dysnomia (officially designated (136199) Eris I Dysnomia) is a moon of the dwarf planet Eris. ... A Small Solar System Body (SSSB) is a term defined in 2006 by the International Astronomical Union to describe objects in the Solar System that are neither planets nor dwarf planets: [1] This encompasses: all minor planets apart from the dwarf planets, : the classical asteroids, (except for 1 Ceres, the... “Meteor” redirects here. ... For other uses, see Asteroid (disambiguation). ... 243 Ida and its moon Dactyl An asteroid moon is an asteroid that orbits another asteroid. ... For other uses, see Asteroid (disambiguation). ... The centaurs are a class of icy planetoids that orbit the Sun between Jupiter and Neptune, named after the mythical race of centaurs. ... A trans-Neptunian object (TNO) is any object in the solar system that orbits the sun at a greater distance on average than Neptune. ... The Kuiper belt, derived from data from the Minor Planet Center. ... Eris, the largest known scattered disc object (center), and its moon Dysnomia (left of center). ... Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ... Artists rendering of the Oort cloud and the Kuiper Belt. ... Astronomical objects are significant physical entities, associations or structures which current science has confirmed to exist in space. ... Below is a list of solar system objects with diameter >500km: The Sun, a spectral class G2 star Mercury Venus Earth Moon Mars Jupiter Io Europa Ganymede Callisto complete list of Jupiters natural satellites Saturn Tethys Dione Rhea Titan Iapetus complete list of Saturns natural satellites Uranus Ariel... It has been suggested that Planetary-size comparison be merged into this article or section. ... This is a list of solar system objects by mass, in decreasing order. ...


  Results from FactBites:
 
Saturn (1430 words)
Early observations of Saturn were complicated by the fact that the Earth passes through the plane of Saturn's rings every few years as Saturn moves in its orbit.
Saturn's interior is similar to Jupiter's consisting of a rocky core, a liquid metallic hydrogen layer and a molecular hydrogen layer.
Saturn's outermost ring, the F-ring, is a complex structure made up of several smaller rings along which "knots" are visible.
Saturn - Wikipedia, the free encyclopedia (2682 words)
Saturn's interior is similar to Jupiter's, having a rocky core at the center, a liquid metallic hydrogen layer above that, and a molecular hydrogen layer above that.
Saturn's usually bland atmosphere occasionally exhibits long-lived ovals and other features common on Jupiter; in 1990 the Hubble Space Telescope observed an enormous white cloud near Saturn's equator which was not present during the Voyager encounters and in 1994 another, smaller storm was observed.
Saturn appears to the naked eye in the night sky as a bright, yellowish star varying usually between magnitude +1 and 0 and takes approximately 29 and a half years to make a complete circuit of the ecliptic against the background constellations of the zodiac.
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